In lighting control systems with distributed or networked intelligent devices it is imperative that unique device network addresses are correctly identified and associated with their relevant locations/areas of control to facilitate correct operational configuration of the system. For example, one current identification method includes using a detachable printed identification (ID) number. An identification number and/or scan able code sticker is removed from the device upon installation and fixed to an installation drawing in its relevant location. This is then later referred to when commissioning/configuring the system.
Another system may use a barcode or other scan-able medium which is removed and affixed to a drawing for later scanning or scanned in-situ and used to directly update information within a commissioning application using software or a handheld tool.
Still further, if the identification of installed devices has not been previously recorded, it is then possible to identify networked devices by pressing a ‘service pin’ (physical button on the device) with a commissioning app/tool in a listening mode. The address of the device is then displayed or assigned to a pre-configured ‘dummy’/virtual device.
A wink function may also be used to facilitate observational identification of luminaires particularly with networked Digital Addressable Lighting Interface (DALI)® addressed devices, which generally do not support the previous methods. The network is scanned for previously un-provisioned devices using a commissioning app/tool and then listed on a screen. A ‘wink’ option button for each of the results is provided and when selected causes the related luminaire to flash on and off repeatedly. When witnessed by the engineer, the device address can then be correctly assigned.
If during the physical installation of an intelligent lighting control system all information regarding addresses and locations has been accurately mapped and added directly to a commissioning application/tool or drawing, the issue of post-installation identification may not generally present a major problem, however from experience this is not always accurately carried out by electricians/installers and physical media such as installation drawings (with IDs attached) can be lost/damaged. Further, when changing devices, or replacing the gateway or the luminaire, the installer needs to follow a long manual procedure that is open to errors.
Visual light communication (VLC) is a known communication technique over Radio Frequency (RF) communication with certain benefits such as high bandwidth and immunity to interference from electromagnetic sources. VLC refers to an illumination source which in addition to illumination can send information using the same light signal. The revolution in the field of solid state lighting leads to the replacement of florescent lamps by Light Emitting Diodes (LEDs) which further motivates the usage of VLC.
VLCs are an emerging form of communication that use visual forms of light emitters to communicate data wirelessly. VLC uses a light source that is frequency modulated, or uses a light source that is turned on and off rapidly when transmitting a communication. VLC systems employ visible light for communication that occupy the spectrum from 380 nm to 750 nm corresponding to a frequency spectrum of 430 THz to 790 THz. The low bandwidth problem in RF communication is resolved in VLC because of the availability of the large bandwidth. The VLC receiver only receives signals if they reside in the same room as the transmitter, therefore the receivers outside the room of the VLC source will not be able to receive the signals and thus, it has the immunity to security issues that occur in the RF communication systems. As a visible light source can be used both for illumination and communication, therefore, it saves the extra power that is required in RF communication. Certain features of VLC include high bandwidth, no health hazard, low power consumption and non-licensed channels.
Some of the applications using VLC, among others, are: Light Fidelity (Li-Fi); vehicle-to-vehicle communication; underwater communication; hospitals; information displaying signboards; visible light identification (ID) system; Wireless Local Area Networks (WLANs); and, dimming systems. Implementation of VLC enabled LED luminaires, in addition to the infrared synchronization protocol, enabled inexpensive white LEDs to be time division multiplexed to avoid packet collisions. Luminaires use token message passing to regulate packet transmission.
Further, VLCs broadcast LED light fixture positioning signals using rapid modulation of light in a way that does not affect their primary functionality of providing illumination. The positioning signals are decoded by smartphone devices using their built-in front-facing camera (image) sensors and are used to compute the device's position in the venue. These positioning signals work like a beacon, which emits information to the environment. Distributed multi-hop visible light communication provides 3600 coverage for directionality, and a flexible design.
For example, for a lighting device to emit location information regarding its environment, the lighting device needs to know its own location. A VLC location inside a room with no GPS access may therefore be required as the GPS cannot be used for accuracy reasons and thus a lighting device does not know its own location. Further, the gateway that uses the VLC/DLC to communicate either knows the location or needs to learn the location.
Further, once the addresses of all luminaire control devices are known along with location information, the next process conducted will be to assign them to operational groups, representing areas such as rooms and corridors. This is ordinarily achieved by manually assigning known addressed devices to a group object so that all members can be controlled by a single command/message when later configured/programmed. As the size of a single lighting control network grows beyond that of a single zone of a floor, to the whole floor, the whole building and areas beyond, the time and labor expended on luminaire/networked device identification will likely be quite extensive. Some typical methods of device identification require some form of direct manual interaction and/or direct observation of the individual luminaire being identified.
Moreover, with the emergence of Internet of Things (IoT) based lighting control systems, the size of a single installation when compared to existing localized networked solutions will grow in size significantly due to the absence of limitations imposed by more localized technologies. As such, an automated method of luminaire location identification using light based communication/VLC/DLC has benefits for reducing the installation and commissioning time for a large lighting-based project.
In view of the above, adaptable and economic use of VLC/DLC in the luminaire industry is beneficial, particularly in Internet of Things (IoT) based lighting control systems. The present disclosure addresses these and other issues associated with VLC/DLC lighting control. For example, sectorized VLC/DLC identification of the exact location of a luminaire relative to a room and to other luminaires and grouping of luminaires based on light based sectorized VLC/DLC modulation technique. Further, automatic luminaire location identification using sectorized VLC/DLC for commissioning a lighting control in very large ecosystems such as a whole building or a floor, in quick turn-around time and reducing manual efforts.